    /* 左右部分 */
    html,body {
        height: 100%;
        margin: 0;
        padding: 0;
    }
    .first {
        width: 15%;
        height: 100%;
        position: fixed;
        border: solid black 1px;
        background-color: black;
        
    }
    .second {
        width: 85%;
        margin-left: 15%;
        position: relative;
        

    }


    #city-img {
        cursor: pointer;
        transition: all 0.2s;
    }
    #city-img img:hover {
        transform: translate(5px,-5px);
        box-shadow: -5px 5px 8px gray;
    }


    #first-nav {
        background-color: #000000;
    }

     #nav {
        position: absolute; 
        z-index: 2; 
        right: 0; 
        font-family: nb-three-font;
     }   

     #show-font {
        position: absolute; 
        z-index: 2; left: 40%;
        color: black;  
        
        writing-mode: vertical-lr;
        font-family: nb-one-font;
        top: 30%; 
        font-size: 69px;
     }
     #section2 {
         background-color: grey;
     }
     #section2-first {
        
        padding-top:50px; 
        font-family: nb-three-font;
     }

     #city-img-two {
         text-align: center;
         margin-right: 0px;
         padding-top: 4%;
     }
     #section3 {
        padding-top:70px;
        padding-bottom:70px;
     } 
     #section2-first-child {
         margin-left: 15px; 
         margin-right: 15px;
        
     }  
     #section4 {
        padding-top:70px;
        padding-bottom:70px; 
        font-family: nb-three-font;
        
     } 
    
     #section2-font {
        text-decoration: none;
        color: black;
     }
     #section2-font p:hover {
        cursor: pointer;
        text-shadow: -5px 5px 8px gray;
     }
     #video {
         margin-bottom: 8%;
     }

     #video-img1 img{
        cursor: pointer;
        transition: all 0.2s;
    }
     #video-img1 img:hover {
        transform: scale(1.1);
    }
    #video-img2 img{
        cursor: pointer;
        transition: all 0.2s;
    }
     #video-img2 img:hover {
        transform: scale(1.1);
    }
    #video-img3 img{
        cursor: pointer;
        transition: all 0.2s;
    }
     #video-img3 img:hover {
        transform: scale(1.1);
    }
    #section5 {
        padding-top:10px;
        
    }
    #font {
        color: black;
        font-family: nb-one-font;
    }
    #img {
        box-shadow: 2px 2px 5px white;
    }
    #bg-img {
        border-radius: 20px;
    }
    #bottom {
        position: absolute; 
        bottom: 0;
        right: 3%; 
        color: white
    }
    